The invention relates to a pulse radar apparatus, provided with a coherent transmitting and receiving unit for the transmission of radar pulses, the reception of echo signals, and the conversion of the echo signals into signals of an intermediate frequency f.sub.if, which may be shifted through a Doppler frequency f.sub.d.
Coherent phase detection of the i.f. signals obtained is widely known. To prevent the effect of blind phases, a quadrature detector is utilised. Such a detector is used to detect the i.f. signal in two mutually orthogonal components I and Q. For further processing in a video processor, these components are digitised. In the cases when the radar receiver is accommodated in the antenna housing and the antenna is rotatably mounted, it is customary to supply the phase-detected signals to the fixedly mounted analogue-to-digital converters and the video processor via a slip-ring assembly. With the use of a quadrature detector, two slip rings are required. If, as with the use of a phase array antenna, a large number of receivers are employed, the number of slip rings is large as well; this is a serious disadvantage. The present invention has for its object to reduce this disadvantage.